Brillouin back-scattering (BBS) in optical fiber may be used as a tool for many applications, including but not limited to, the sensing of local temperature and/or strain. The frequency shift associated with BBS is a function of both the temperature (T) and strain (σ) applied to an optical fiber. If a pulse of light is sent down a fiber and time-gated returns are analyzed with respect to what was launched, the distribution of frequency shifts as a function of distance can be determined. This frequency shift is usually influenced by both the strain and temperature effects which co-exist in a fiber. Thus, to distinguish the local temperature from the strain, two fibers can be employed which have differing responses to each of strain and temperature. This gives rise to a system of two equations and two unknowns, from which the individual strain or temperature can be determined. Alternatively, a fiber can be specially-sleeved in a loose manner to remove strain effects and measure just a local temperature. Both approaches lead to more expensive and complex measurement systems.